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Comments 151 to 175 out of 318:

151. LandyJim at 11:59 AM on 18 January, 2011
     I'll set my stall out with my first post. I am not a believer in anthropogenic climate change, the arguments put forward are weak in my opinion and I think much of the real science may have been left behind or fudged to fit, however I have an open mind and am up for any scientific proof that my stance is wrong... ghornerhb: Regardless of the comments on this site about the other planets, please don't be fooled into the "other planets are getting hotter" argument, it has no merit. Jupiter emits ~2.5X the heat it receives from the Sun due to gravitational contraction and Saturn is in a similar position, we know so little about what is going on in these planets that making statements about their weather is like claiming Jesus would have liked Take That. Uranus and Neptune are even less understood, however both planets are fast approaching their closest approaches to the Sun in their respective orbits, so again, the argument has no validity. Mars, we know too little about Mars to make any realistic assessment of what it's climate is doing, just when modellers think they have it, up pops some variation from their model and they are back to square 1. Venus...OMG..I get really peeved when both sides of the climate fence try to use Venus to either scaremonger or cite evidence that the planet is getting warmer. Venus and Earth are very similar in physical size...there it ends. Earth and Venus NEVER had similar atmospheres, regardless of what some people imply. Earth is 78% N² and always has been within a few % of that figure, the H²O, CO² and other gases have varied over time and the O² content is a major pollutant put into the atmosphere by life about 2.5-3 billion years ago, without it the CO² content would likely be several% to 10% with water vapour and Methane (CH4) filling the rest of the gap. Venus has an atmosphere that is composed of 98% CO². Even if Venus had large bodies of water at one time, they are long gone and the atmosphere, being 93X the mass of Earth's is what helps to keep Venus so warm, not just the fact that CO² is a greenhouse gas. Comparing Earth and Venus is like comparing Gandhi and a T-Rex. Earlier in this thread there was talk of the impact of water vapour in the atmosphere and the fact that it is potentially a major greenhouse gas, but this is actually ignoring it's major influence on the atmosphere..it results in clouds...and clouds reflect solar radiation back into space increasing the albedo of Earth and thus cooling the surface. It's not as simple as that sentence makes it sound, they also can act like a blanket locally too, but then it is not as simple as the IPCC have made it sound either. There is no doubt that changes in solar output will impact Earth and thus the global mean temperature (GMT). There is correlation between sunspot activity and the climate, although this is very poorly understood at this time. Another factor many modellers fail to account for is the motion of the Earth in space. The Earth has an odd orbit, caused by the fact that it is not a true single planet, but then it is not a true double planet either. The relationship of the Moon and the Earth is complicated and that the Moon is a major influence on our planet is poorly understood, but it does impact the axial rotation of the planet, it impacts the tilt of the axial rotation over time, and it impacts the way in which the Earth-Moon system orbit the Sun. Earth's orbit in space suffers from precession, meaning that the point of closest approach (perihelion) actually moves around the orbit over time, it takes about 30,000 years to complete one "orbit" of the Sun. The Earth's orbital plane also suffers from precession, it drifts up and down in a period of about 70,000 years. The tilt of the planet (known as obliquity) varies over a roughly 41,000 year period from 22.1 to 24.5 degrees. There is a theory (Milankovic) that was proposed back in the 1920's that these cycles impact the climate of Earth and may be responsible for Ice Ages. The theory was unprovable back then, but in the 1960's and the 1970's deep Ocean cores were studied and a seminal paper by Hays, Imbrie, and Shackleton, "Variations in the Earth's Orbit: Pacemaker of the Ice Ages", appeared in the distinguished journal Science in 1976. Anyone interested in reading this can do so. http://www.mantleplumes.org/WebDocuments/Hays1976.pdf This paper provided crucial evidence to the theory and leant it considerable weight which has not yet been refuted. What I am saying is this, I do not see evidence for anthropogenic climate change simply because we live on a planet with the some of the most complicated weather we know of and we know too little about the influences and interactions on it to make any definitive judgements on it and out impact. This is not to say I am against cleaning up the "rubbish" we dump into the air, I am all for that, regardless of reason, I just want to ensure that any decisions made are based on solid common sense and science, not mumbo jumbo, pseudo science, snake oil or scaremongering.
     Response: There are other threads that are more appropriate for most of your points. I don't have time now to point you to them, but everyone who responds, please do so on those other threads, with a simple sentence with a link here.
152. Clearsight at 15:34 PM on 4 February, 2011
     It seems that you have alot of scientific information that mis-intreperted, could result in mistaken understanding. I believe that is what is going on in the world today. The simple facts are that 70% of our oxygen comes from phytoplankton found in the ocean. Coral reefs remove about 33% of the world's carbon dioxide. Temperatures have been steadily increasing for the past decade. They are finding that the plankton are living deeper than before. The photic layer of the ocean only extends so far, if we loose the plankton, 70% of the world will die. Coral reefs are bleaching (temporarily dying) at an alarming rate. I have worked outside for 30 straight years and I know it is getting hotter. I have 4 college degrees, two science minors, one B.S. in Zoology, and an IQ of 136. I fininshed in the top 8% of all of my military and college analytical classes. In junior high on the Standford Achievement Test I scored in the top 8% of the entire state in both mathematics and english. I finished top of my critical logic and reasoning class. I am convinced with every fiber of understanding in me that global climate change is happening and if left unchecked, there will be catastrophic events.
153. Marvin Gardens at 00:53 AM on 6 February, 2011
     Clearsight @ 152 Why are the plankton living deeper? Doesn't make sense for them to try and live somewhere they can't. With all your degrees and smarts you should be able to spell Stanford. ;)
     Response: [Daniel Bailey] This offers up a good summary of the 40% decline in oceanic phytoplankton since 1950.
154. Will Lowry at 06:10 AM on 12 February, 2011
     While wild climate change has preserved a delicate balance of gasses called the atmosphere and has been very good for life on this planet, human caused climate change is new, and scientists agree it will soon upset that balance and have catastrophic consequences for human life.
155. Magpie at 04:56 AM on 6 April, 2011
     What I said in a recent conversation on this topic: "Look, even if it's true that it was just as warm in medieval times, that means we've had a thousand-odd years of climate change in just a few decades, and the rate of change only looks to be increasing. How is that supposed to be a good thing?" Seemed to have an effect. Sometimes people have all the information needed to come to a logical conclusion, they've just been using that information as sponge and padding to protect their fallacy.
156. trunkmonkey at 02:40 AM on 8 April, 2011
     Indulging in a little attitude I find efforts to cast the PETM as a paleo fossil fuel burning event caused by the rifting of Greenland from North America utterly preposterous, right up there with the giant gymnosperms rototilling the Ordovician soils to foster weathering and beds of gravel preventing pre-Wisconsin ice sheets from attaining any thickness! One can readily observe from weather satellites that no great billows of smoke are coming from the current rifting in the Red Sea-Gulf of Aden-African zone, nor in the Gulf of California, all fossil fuel rich areas. Furthermore, the rifting of Greenland away from North America and Eurasia was well underway at the end of the Cretaceous.
157. ciclista at 05:08 AM on 23 April, 2011
     Looking back for some millions of years, earth atmosphere generally showed concentrations of CO2 much higher than today. This leads me to expect much higher average global temperatures in former times too. However, talking in timescale of millions of years, the perspective of strong correlation between temp end CO2 does not match that perfectly like date published from the ice cores, that go 400.000 years back. Especially for the period about 450 millions of years ago, when there were temperatures like today, although the CO2 concentration was 10 times today´s value. How can this low temperature be explained. Vulcanoes? Can anyone help me to understand?
158. KR at 05:18 AM on 23 April, 2011
     ciclista - A good question, which has already been discussed on this website in the Does high levels of CO2 in the past contradict the warming effect of CO2 thread. Long story short - CO2 has been higher in the past, but other forcings have a history too. The sun was dimmer hundreds of millions of years ago (about 4% during the period you mentioned), and the combinations of forcings including CO2 and sunlight match the climate record. See also CO2 is not the only driver of climate.
159. CBDunkerson at 05:20 AM on 23 April, 2011
     ciclista, see CO2 was higher in the past. Basically, the Sun puts out more energy as it gets older. Thus, since CO2 and other greenhouse gases (GHGs) act to retain some of the Sun's energy within the climate system a fainter Sun means more GHGs were needed to have the same temperature.
160. E Sat at 21:00 PM on 16 May, 2011
     I read the comments of Quietman and I feel refreshed. You are able peel a lot of the scientific language away from many of the theories like the skin of an old banana. What is left behind is not worth digesting. I really like the sections about the people you have labelled "Nemesis hypothesis' writers. There are always some people out there who reckon the world will end tomorrow and we are the cause. We took years to learn that there is an El Nino - La Nina cycle. Before that we just had bad weather and managed to live through it. What about the effects of the many wobble cycles of the Earth's axis? We are only beginning to understand their effects now. Why do we have to panic whenever a new piece of science causes the alarms to go off, bringing our day of doom even closer? I am sometimes forced to think that there are times when there is too much science out there for our own good. This is an ironic point to take, I suppose, as I am using the Internet to post this comment. How are we meant to be able to tell what is an honest scientific theory from one that is popular just because it has been better financed and makes better sales for the media? We know that the climate is changing and we know that it has changed before but isn't a bit arrogant to think that at this exact point in time we are in a position to predict the climatic future of our planet?
     Response:

     Welcome to Skeptical Science!  There is an immense amount of reference material discussed here and it can be a bit difficult at first to find an answer to your questions.  That's why we recommend that Newcomers, Start Here and then learn The Big Picture.

     I also recommend watching this video on why CO₂ is the biggest climate control knob in Earth's history.

     Further general questions can usually be be answered by first using the Search function in the upper left of every Skeptical Science page to see if there is already a post on it (odds are, there is).  If you still have questions, use the Search function located in the upper left of every page here at Skeptical Science and post your question on the most pertinent thread.

     Remember to frame your questions in compliance with the Comments Policy and lastly, to use the Preview function below the comment box to ensure that any html tags you're using work properly.

     Actually, most of the effects you describe in your comment are pretty well-understood.  That the planet is warming is now considered an established fact.  That humans are the principal cause behind most of the warming since about 1970 or so is very likely (greater than 90% likelihood).  All that's left to be determined is how much warming is to come - and how soon - and what its attendant effects will be.

161. JMurphy at 22:05 PM on 16 May, 2011
     E Sat wrote : "We know that the climate is changing and we know that it has changed before but isn't a bit arrogant to think that at this exact point in time we are in a position to predict the climatic future of our planet?" No arrogance involved at all - simply what we as a species should be proud of : The human search for answers, using rational, scientific methods. No-one should be arrogant enough to think that all the answers can be found but surely we should give the experts a chance (and our backing) to do their work without constantly judging them according to our own personal criteria ?
162. Riccardo at 23:35 PM on 16 May, 2011
     We humans might be said to be arrogant because we've tried to fly, or because we think we've found the origin of the universe, or how life evolved on our earth, or almost anything we understood with the tools of science. If working hard to find answers to our questions means being arrongant, then yes, we are a very special kind arrogant animals.
163. DSL at 00:08 AM on 17 May, 2011
     E Sat, I'm assuming you're not a bot. We studied the oscillations, the wobble, the sun, the whole nine yards. Science did that. Now we understand a great deal more than we did, and it didn't take that long to understand these environmental features. When we discovered ENSO, there were no cries of doom and gloom, nor were there when the wobble was discovered. Why? Because the science said these things were not likely to be catastrophic. We've been working on the CO2 problem for about 130 years, since Arrhenius. The alarm has only grown in the last 30 years, since we've begun to observe and measure accurately the changes required by the physics. That's right: the changes are required by the physics, or else we need to toss aside everything we know about physics. The funny thing is, though, that climate science is, in one aspect, a social science. It does not serve the market. If there were no governments, there would be no climate science, because no one would want to spend money on making long-range climate forecasts. Even if a business collective formed an institute to study the climate, it's unlikely such an entity would have much of a social effect. The collective would simply treat the information as private and use it to make market decisions. I'm sure a few backyard scientists would figure things out, but to what effect? I can't, then, think that there's "too much science" out there. Climate science serves me, with no other agenda. Contrary to rumor, climate scientists are not swimming in coin--unless they go private. There's not much benefit to them if they predict a warmer future. As I've said elsewhere, when governments begin to spend serious money on mitigation and damage control, other government services will suffer, including public higher education. It's entirely possible that within 20 years, a number of university climate science positions will be cut as an indirect effect of the changing climate. How can you tell an honest scientist from the deceivers? Study. Spend some time with Spencer Weart, this website, and the studies linked from this site. Even if you don't have the time to do the math, you can get at least a glimpse of the answer to your question by comparing the rhetoric here to that of a leading "denialist" site like Watt's Up With That. You won't see a lot of evidence-free cheering and jeering here, and you won't see a comprehensive alternative theory there. What you should look for is a consistent, comprehensive theory that tries to explain all the observational data and incorporates everything we know about the physical universe. There is only one such theory where the climate is concerned (unless you're hiding one in your back pocket). Finally, it would be arrogant of us to assume that the economy of billions of people over 200 years would have no effect on the environment. I think you know it has and it does. But why single out this particular effect for falsehood?
164. PhillyWilly at 12:14 PM on 31 May, 2011
     The Earth has always had a TOA imbalance, it'll always have one. 1) Looking at the Arctic and Antarctic Ice Cores, both clearly show todays temperature has been exceeded in those regions by 1-2C in the past due to natural factors. Also knowing the "Methane Feedback" that would occur in that circumstance, or a general positive feedback, would have a global impact. 2) Tree ring proxies are aweful, and are often used in reconstructions to temperature. Thats a problem. 3) Why are we using CO2 data from Ice cores before 1960, and not the 80,000+ bottle measurements? These clearly show a higher CO2 level, around 335ppm, from 1920-1950, some higher, some lower, but the mean is clustered.
165. scaddenp at 13:17 PM on 31 May, 2011
     1/ - but those natural factors are not is causing the current imbalance. The imbalance is from increasing GHG. 2/ - proxy reconstructions without tree rings deliver the same picture (esp ice core). 3/ - low accuracy measurements in polluted cities are exceedingly poor proxies for real atmospheric CO2. If you are referring to Beck's nonsense, then please see the link in this for some real analysis.
166. PhillyWilly at 14:04 PM on 31 May, 2011
     1 Yes Partially correct..Its indeed part of the TOA imbalance, but the TOA imbalance includes more than just the CO2 spectrum. NOAA/CPC both show increasing avg outgoing LW radiation...indicating that there is natural warming going on as well: http://www.esrl.noaa.gov/psd/data/gridded/data.interp_OLR.html Note the Increase is by several W/m^2, in fact it has increased by about 3W/m^2 since 2002, and since 1980 there has been an overall increase. That is not only indicative of nautral warming from the planet (not caused by CO2), but also a negative feedback since 3W/m^2 is more than the 1.6W/m^2 cited by the IPCC since 1790, which should supposedly due to positive feebacks have amplified to the 0.8C we've increase we've seen, since per Doubling the increase in temps is progged around 1.2C. The changes in CO2 energy increase has been significantly less than the obsevred OLR change in the time we've measured, and we've likely mis-represented the feedbacks to CO2 warming. 2) No they don't actually, although it depends on the tree-rings used. Ice core proxies show the polar temperature to have been warmer by 2C at time in the past...so if Tree ring proxies show the same thing...why are the similarities invivible??? 3) What makes you think these CO2 measurements were taken only in "polluted cities"? And no not referring to "beck", but more of the measurements in geenral. Do you know what happens to data trapped in Ice Cores over time? take a guess :-)
167. scaddenp at 14:43 PM on 31 May, 2011
     1/ I agree TOA energy imbalance includes all sources of energy, but there is no way to infer from OLR that there natural warming going on. In contrast, the spectral signature of OLR matches the expected spectra for OLR. An increase in OLR W/m2 just tells you planet is warming. By itself this tells you nothing. Energy balance is difference with energy in and that is what we expect. This is a very confusing argument. 2/ Look at the whole list of proxies available in WG1 report, with and without tree proxies. The different published proxies vary in detail but support a consistent picture. We are getting hotter. 3/ Please provide a reference to these. The usual source of this argument is EG Beck's collection of old references. Got a better reference. All proxies have problem, ice data just happen to be among the best. What's your reference for problems with ice bubble data that you think allows for a different interpretation?
168. scaddenp at 14:56 PM on 31 May, 2011
     Just to add to comments on CO2 measurement, you might like to look at this on measurement of CO2 in general and problems with the old chemical measurement. Further Keeling, responded to Beck's stuff with this comment. "It should be added that Beck's analysis also runs afoul of a basic accounting problem. Beck's 11-year averages show large swings, including an increase from 310 to 420 ppm between 1920 and 1945 (Beck's Figure 11). To drive an increase of this magnitude globally requires the release of 233 billion metric tons of C to the atmosphere. The amount is equivalent to more than a third of all the carbon contained in land plants globally. Other CO2 swings noted by Beck require similarly large releases or uptakes. To make a credible case, Beck would have needed to offer evidence for losses or gains of carbon of this magnitude from somewhere. He offered none. " Are you sure that measurements you refer to dont run foul of same issue? (mass balance).
169. u4486662 at 13:42 PM on 20 June, 2011
     There is no sceptical argument that climate has changed in the past and therefore can't change because of humans. The sceptical argument points to times in the past when the earth has been much cooler and CO2 levels were much higher than they are today. It also points to the various known contributors to climate change and the complexity in which they interact. CO2 is a secondary greenhouse gas and theoretically therefore can absorb infrared light and hence heat - but of course its far more complicated than that. The net effect of cloud formation is cooling not warming and this is likely to effect projected models. CO2 has risen from 0.02% to 0.039% since the industrial revolution. The belief that the CO2 rise has led to a radiative forcing level of 3.7W/m-2 is debatable in itself. Of course you use the IPCC reference which assumes a climate sensitivity level of CO2 of 0.8K. The key word is assumption and its what most of the models are based upon, assumption. There are many other credible sceptical arguments which provide a counterpoint and healthy debate should continue. Its important to remember that sceptics are not anti-environment as some posters say but in fact I am pro-environment. Poverty in Africa is causing more damage to the environment than industrialisation and development would.
     Response: (DB) Nice Gish Gallop. Pick the point you feel the strongest about, use the Search function to locate the most appropriate thread and post just that point there; someone will get back to you very quickly.
170. Bibliovermis at 13:56 PM on 20 June, 2011
     "Belief" pegs your intent. All of your points have already been addressed on this site, with direct references to primary source material. Healthy debate is occurring constantly. Denial and willful ignorance of the accumulated scientific knowledge is not a means of healthy debate. e.g. argument #51: Does high levels of CO2 in the past contradict the warming effect of CO2? The Ordovician glaciation was a brief excursion to coldness during an otherwise warm era, due to a coincidence of conditions. It is completely consistent with climate science. argument #96 CO2 is not the only driver of climate Theory, models and direct measurement confirm CO2 is currently the main driver of climate change.
171. kiwipoet at 10:13 AM on 30 June, 2011
     Bear with me, bloggers, as this is my first post to SkSci, in fact my first post ever. I would like to make a comment on E Sato’s post in this thread of May 16, as there is a story behind it. I teach writing at a NZ university, and gave a stage 1 (first year) English class (three tutorial groups, actually, about 60 students) a copy of the graphic that shows 97% of climate scientists acknowledging AGW, with media acceptance about 48% and the general public about 46%, and asked the students what conclusions they could draw from the data. (Sorry don't have link handy.) I further challenged the students to check out the SkSci site and a denier site, such as WUWT. The graphic produced a fierce discussion. About half the class seemed to get the point, although almost no one suggested that the monopolistic ownership of the media might be a problem. I should have been prepared for it, but I was quite shocked at the degree of confusion and fallacious thinking evident, with some truly ridiculous things being said. One student even suggested that climate scientists were terrorists of a kind. A student from India got angry at the idea that I was suggesting countries like India should curb their emissions while the ‘developed’ countries go on their merry way, while I had said nothing of the kind – I was solely concerned with the issue of scientific consensus. Anyway, of all the students E Sato was the only one to take up my challenge and post SkSci. E Sata describes herself as a second language learner, which explains some of her English, but aside from that the confusions evident in her post do reflect to some extent the more general confusion among the students. It seems that attitudes to possible solutions to AGW get conflated with the science of the issue: In other words, if you don’t like the tax, reject the facts! I came away from these classes thinking, rather gloomily, of that wonderful quote from Adorno, in his Minima Moralia: "The conversion of all questions of truth into questions of power has attacked the very heart of the distinction between true and false." (page 15, recently quoted but not referenced by Al Gore in his Rolling Stone article) A further thought. The words ‘science’ and ‘scientist’ have in themselves become a kind of mental block; after all it was ‘scientists’ who told us nuclear power was safe, ‘scientists’ who told us genetic engineering would feed the poor and not just make Monsanto rich. When talking with deniers I no longer use the words ‘science of global warming’ but rather refer to the evidence or the facts and try to leave the S word out of it. Finally, with regard to the subject of this thread (!), It seems that the ‘climate has changed before’ argument, most prominent among the students, is a refuge for those who know nothing about the issue at all, who wouldn’t know a Moncton from a Monbiot, and is therefore difficult to deal with. Denial, as we are starting to realize, has deep emotional and ideological roots. Voltaire said it all in four words: ‘men argue, nature acts’.
172. Stephen Baines at 15:02 PM on 30 June, 2011
     That's really interesting kiwipoet. I think there are some important observations here that I have observed myself, albeit in a less obvious way. I wonder if you should post this in another thread where it might be more relavent - maybe the consensus image thread or another concerning communication of climate science. Any advice moderators?
     Response:

     [DB] Several come to mind, chief of which is probably this one:

     Infographic: 97 out of 100 climate experts think humans are causing global warming

173. kiwipoet at 09:41 AM on 4 July, 2011
     Thanks Stephen Baines for your encouraging reply. I replied on this threat because that’s where E Sat’s post appeared. I will take the advice of the moderator, make some changes to the post, and place it on the infographic thread. Thanks moderator! A final thought, however, on the ‘climate’s changed before’ argument. By using the term ‘natural climate forcings’ for what we can observe in the past as opposed to ‘man-made’ global warming now, we reinforce the division between man and nature that has helped precipitate the crisis. (Anthropocentric is better word technically but doesn’t avoid the problem.) It seems important to stress that man’s activities are as much a natural force as any other. We are the volcanoes of the age. It is because we are an intrinsic part of nature that we can have such a profound impact on the planet. By accepting language that separates man from nature we are, conceptually, partly buying into the denier illusory worldview.
174. DougCotton at 20:59 PM on 6 July, 2011
     There is now statistically significant Fourier transform analysis which detects 60 year cycles in temperature data. There are also obvious other cycles, notably one of about 934 years. These cycles also correlate with planetary orbits as I have explained at earth-climate.com and so we now have proof that gravity from the sun and planets affects Earth's climate. Predictions are for slight cooling till 2028, then warming to 2059 then long-term (934 year) cycle is at maximum and so a long term decline to Little Ice Age conditions about 450 years after that. There is a detailed explanation and reasons on my site. I am happy to answer questions to my email address thereon.
175. les at 21:08 PM on 6 July, 2011
     174 - DougCotton And if anyone says there is no physics basis for planetary orbit driven cycles, and cycles within cycles... just show them this

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